help...

I feel like I've lost all ability to connect with other people after my ex destroyed me. 4 years into our relationship and we got engaged only for me to find out he was cheating the whole time. this was about 4 months ago. I was so open and vulnerable with him. he knew everything about me and we could talk about *anything* for hours. the conversation never got boring. now it feels like I never know what to say to anyone. I don't have many friends and even connecting to them anymore feels awkward and forced. I just feel so alone and like my brain has turned to mush. how do I hold a conversation anymore? how do I move on when talking to guys is like pulling teeth?